Thumbs up for feral tank.
With that aura they pass out " passive healing" based on total help is a great addition, although you could have it as a kitty. I ran into the same thing in moving from a pally to a druid, its just a different type of tanking style.
I think passive healing would indeed be more targeted to a tank with large hp pools instead of smaller ones with more mitigation, as passive healing is chance for the most part.